Steam for Linux

I just got selected for the Beta and tried to run TF2. Because i'm using an AMD A8 3870K without a extra graphics card, i wanted to test if the newest beta Catalyst 12.11 Beta (The changelog said something about LFD2). With version 12.10 Steam is running normally (I didn't test the Big Picture Mode) and TF2 is also running (It only takes ages to load).

With the latest Beta Steam doesn't even start. It crashes even before the login-window appears: